氮掺杂TiO_2的冲击合成及可见光催化活性研究  

Shock Synthesis of N-Doped Titania and Its Photocatalytic Activity under Visible Irradiation

作　　者：刘建军[1] 张红玲[1] 陈鹏万[2] 高翔[2] 崔乃夫[2] 

机构地区：[1]北京化工大学理学院,北京100029 [2]北京理工大学爆炸科学与技术国家重点实验室,北京100081

出　　处：《高压物理学报》2013年第1期51-56,共6页Chinese Journal of High Pressure Physics

基　　金：国家自然科学基金(10972039;10972025)

摘　　要：冲击相变及冲击诱导化学反应可导致材料的物理、化学性能发生显著改变。采用炸药爆轰驱动飞片高速碰撞产生冲击波的方法,对富氮掺杂物双氰胺(C2N4H4)与P25TiO2或偏钛酸(H2TiO3)的粉末混合物进行冲击加载,对回收产物进行X射线粉末衍射、透射电子显微镜、X光电子能谱、比表面积及紫外-可见漫反射光谱表征,通过亚甲基蓝和罗丹明B评价了回收产物的可见光催化降解活性。结果表明:以P25TiO2为原料的冲击氮掺杂浓度可达8.88%,掺杂样品具有明显的可见光吸收,能带宽度减小到1.75eV,样品中形成了少量Srilankite高压相;而以偏钛酸为原料的冲击氮掺杂浓度为3%～4%,能带宽度变化较小,但是由于其独特的冲击脱水膨胀机理,比表面积剧增。冲击氮掺杂样品对亚甲基蓝和罗丹明B染料有较好的吸附和可见光催化降解作用,其中高飞片速度处理的样品有更高的光催化降解活性。Shock transformation and shock-induced chemical reaction in materials can lead to their obvi- ous changes of physical and chemical properties. In this paper,the powder mixtures of nitrogen-rich of C^N4H4 and P25 TiOz or metatitanic acid were shocked by the impact of flyer plates driven by explo- sive detonation, and the recovered samples were characterized by X-ray diffraction, transmission elec- tron microscopy,X-ray photoelectron spectroscopy,Brunauer-Emmett-Teller （BET） surface area anal- ysis and UV-Vis spectra and evaluated by the photocatalytic degradation of methylene blue and Rhoda- mine B. The results indicate that the doping level of nitrogen-doped TiO2 reaches 8.88% （atom frac- tion） using the P25 TiO2 as raw materials which exhibits obvious absorption in visible region. Its ener- gy gap decreases to 1.75 eV together with the formation of srilankite high-pressure phase. The doping level is 3^-4~ （atom fraction） corresponding to the small variation of the energy gap using the meta- titanic acid as raw materials. The specific surface area of the sample increases dramatically due to the unique shock dehydration-expansion mechanism. The nitrogen-doped TiO2 have better adsorption capa- bility and photocatalytic activity under visible irradiation for the degradation of methylene blue and Rhodamine B,among which treated at higher impact velocity shows the higher photocatalytic activity.

关 键 词：二氧化钛 冲击合成 氮掺杂 光催化降解 

分 类 号：O521.23[理学—高压高温物理]